@misc{Darwin_Charles_Robert_(1809–1882)_The_1876,
 author={Darwin, Charles Robert (1809–1882)},
 copyright={Public Domain},
 address={New York},
 howpublished={online},
 year={1876},
 publisher={D. Appleton and company},
 language={eng},
 title={The variation of animals and plants under domestication. Vol. 2},
 type={Text},
 URL={http://www.rcin.org.pl/Content/130743/PDF/WA488_160493_20125_Darwin-Variation-animals.pdf},
 keywords={Heritage - atavism - fertility - laws of variation - hybridism - hypothesis of the pangenesis},
}